How can mining be more environmentally friendly?
Bacteria can be used to mine
Acidothiopacillus ferrooxidans (a bacteria that can live under acidic conditions) can be used to mine gold, copper, etc. I think (I need to check) there are more than 5 mines around the world they use this system. It is better than cyanide method since it does not cause water or soil pollution. It is better in terms of metal recovery. However, you need a system that should be under control (temperature, pH, pressure, etc.) to use this type of bacteria.